I use to take my M675 to work each and every day for the past year. Ran for 9 hours or longer at work and when I got home, it was on for around 3-5 each night. I took it everywhere using a backpack to offset the weight.
I work at home, and I love being able to go from my desk to in front of the living room window on those sunny days. On days when I need to get out of the house, I go over to my brother's place and sit out in the backyard and work. I can't imagine going back to a desktop system.
I bought my eMachines m2350 to take to work temperarily. For the next few months I'm kind of between assignments and in a period of "training", which looks like will be synonymous with boring. Hopefully having this thing with me will keep me sane. Problem is, now that my wife has seen it she wants one too.